The French Laundry, Napa Valley’s most renowned food destination, is famous for its slow, luxurious meals. But this weekend, in honor of the restaurant’s 20th anniversary, ChefThomas Keller and his staff dished up the longest one yet—a six-hour feast for friends, locals, and luminaries. Keller was featured in an August Portrait in Vanity Fair, photographed by Annie Leibowitz. Keller described the event as “a sophisticated, elegant block party,” where guests mingled, nibbled, and sipped under the leafy branches of the California oaks and sycamores that line the block in front the building that has, for the past 20 years, served up fun riffs on classic cuisine. The menu on Saturday was no different; treats ranging from “down home” grilled-cheese sandwiches stuffed with delicacies (“You have to have truffle, right?” joked Keller), to individual jars of caviar and panna cotta were all offered up under the twinkling lights and dangling charcuterie displays.

Despite the French Laundry’s hallowed reputation (reservations are notoriously difficult to attain, and the meal itself is a multiple-hour event) this party wasn’t a stiff affair. Event planner Todd Fiscus explained Keller’s approach:

“It’s not serious, it’s not a library. You don’t have to whisper tonight. Tonight you get to dance. You know, sometimes you eat these beautiful dinners and you feel like you’re in a shrine to brilliant food, which is really not Thomas’s style. Tonight it’s much more celebratory than that.”

In addition to the food stations and free-flowing Moët & Chandon and specialty cocktails, the young French Laundry staff circulated the party with some of the restaurant’s more classic bites, including the famous salmon tartare cornets (find the recipe here). The friendly staff who are famous, Keller says, for being “confident enough to let that personality shine through,” offered every new treat with a grin and a cheeky comment. “Don’t say no! How could you?”

The staff themselves were treated to their own family treat before guests arrived. It’s tradition, at the French Laundry, for the fanciest chefs and servers in California to chow down on a meal of In-N-Out Burger prior to any big event. Chef Keller joked:

“We either want to treat everybody or sedate everybody with protein and carbohydrates. In-N-Out is just tradition and we really stay connected to our traditions. We love having one foot in the past and one in the present.”

Once the guests arrived, they strolled into the restaurant garden, careful not to muddy their party shoes, or leaned out over the balcony of the restaurant that over-looked the festivities below. For the most part, elbows were rubbed—Congresswoman Nancy Pelosi and filmmaker-turned-restaurateur Francis Ford Coppola exchanged pleasantries with the restaurant’s Yountville neighbors—and the only slight throwing of elbows came when a fresh round of truffled grilled cheese came off the grill.

The specially designed French Laundry 20th anniversary double X logo adorned everything, from cups, to ice sculptures, to the specialty Mast Brothers chocolates; it was even branded into the shank of the aged, artisanal meat. Guests needing a break from all the culinary treats could stroll over to the cigar station where the so-called cigarmelier would hand select the perfect brandy to pair with your smoke; the cigar bands, naturally, were emblazoned with the ubiquitous XX.

As the evening started to wind down, Keller was treated to a video roast of sorts put together by his fiancée Laura Cunningham. Keller was teased and toasted by staff as well as celebrity friends like Ryan Seacrest, Daniel Boulud, andJacques Pépin. Adam Sandler, who worked with Keller on the film Spanglish, slurred his congratulations while curled up on a couch. He thanked Keller for all the great food and wine and praised him for “20 years of getting people drunk.” As the French Laundry staff hooted and clapped for inside jokes, we were once again treated to the feeling of being at a close, family gathering. Keller explained that’s just what he had hoped for:

“In the end you realize success isn’t about fame and fortune, it’s about having beautiful memories. I think that, for me, is the most meaningful thing about this celebration. It’s a celebration about a restaurant that has touched so many people’s lives.”

But if it is a close family gathering, it’s the most elegant one you’ll ever attend. Fiscus boils it all down:

“There was a gentleman polishing the copper door to the kitchen at 10 minutes to shift. The kitchen door in the back, nobody was going to see it. Guests weren’t going to interact with that door. That is French Laundry to me. Nothing is unattractive. Not the pantry, not the kitchen, not the workspace, not the garden, not even the backdoor to the kitchen.”